1. Field of the Invention
The present invention relates to a continuous process for making carpet face yarns made from two fiber types, and more particularly, to combining singles yarns of higher denier with singles yarns of textile denier to produce face yarns with special color effects and appearance, including improved processes and new products therefrom.
2. Description of Related Art
As used herein, certain terms have the meanings ascribed to them as follows:
The terms "thread" and "filament" are intended to connote single filament fibers, whereas "singles yarn " or "strand" is an assembly of two or more fibers.
The term "node" is intended to mean relatively compact, tangled sections of a yarn that are separated by relatively bulky or unentangled sections. The term "entangling" is intended to mean the mixing of components to an extent that the individual components cohere to one another, where "cohere" means to stick or hold together in a visually identifiable and distinguishable mass, an example of which is the above-mentioned "node". Entangling includes directing a flow of fluid, such as air, against a moving plurality of filaments transversely of the direction of movement of the filaments. The resulting dislocation of the filaments leads to a knot-like intertwining and entangling of the filaments or strands. The term "air-jet entangler" is a device which produces an entangled yarn by co-mingling the components of the yarn.
A "texturing process" causes a permanent departure from the original longitudinal shape of the filament, for example, by causing the filament to be crimped, or to have some degree of curved or angular change along its length. One example of a texturing process employs a chamber in which yarn is moved at high speed through a flow of heated gas or vapor, i.e., hot air or steam. Alternatively, heated or unheated yarn may be moved at high speed through a mechanical crimping process. The yarn may then be bulked by collision with a surface which, for practical purposes, may be the wad or plug formed by the yarn itself. As a consequence, individual yarns deposit themselves in a bent configuration on an impact surface, and because of heat-induced effects, the yarns retain, to some extent, this curved or angular configuration. When the texturing is accomplished using a heated yarn, the crimped fiber configuration is made permanent by a cooling process, without permitting portions of the yarn to adhere, or be connected, to each other.
A continuing need exists for fiber and yarn producers to offer carpet, floor, and wall covering designers yarns that will provide a unique appearance or will provide unique performance characteristics once tufted, woven, or knitted into pile fabrics or carpet.
Significant resources have been devoted to the manufacture of yams which have unique attributes. Such yarns have included combinations of fiber building blocks, i.e., singles yarns, of different polymers, fiber cross-sections, fiber denier, or color. For example, U.S. Pat. No. 3,604,197 describes yarns made from a blend of fibers, of the same polymer type, in which one component is a fiber of one particular denier and color, and the other component is of another particular denier and color, where the lower denier component makes up the majority of the final yarn.
U.S. Pat. No. 3,802,177 describes multicolored yarns made from one fiber type of round cross-section and one color, and another fiber type of non-round cross-section and another color. The round cross-section fiber is the majority component, with the non-round component serving as an "accent" yarn. It is significant to note that the patent emphasizes that the desired effects can only be achieved by this particular yarn combination.
Other prior patents disclose various approaches to producing yarn blends or mixtures that will, when tufted into carpet products, provide specifically desired attributes. Examples may be found in U.S. Pat. Nos. 3,994,122; 4,226,079; 4,472,481; 4,712,366; 4,882,222; 4,993,130; and 5,413,857.
While the prior art, typified by the above-noted patents, may provide a range of products of use to the carpet stylist or wall covering designer, such products do not address the problems currently being faced by the industry and for which adequate solutions have not been found. In particular, there is a continuing trend within the industry toward producing carpets and other pile fabrics with lower face weights. The move toward lower face weights has generally led to carpets that have high tuft density and smaller yarn bundle sizes. Concurrently, this trend is seen as leading to reduced color complexity, at a time when the exact opposite is being requested by stylists, as it becomes more and more difficult to have high numbers of larger denier singles yarns in the final face yarn. In this respect, it is noted that a recognized pleasing and effective aesthetic is the interplay contrast between chromatic color(s) and the neutrality of surrounding or adjacent color(s). The smaller the yarn bundle, the sharper and more dramatic the contrast.